Paulo Costa Revives Rivalry with Khamzat Chimaev

Paulo Costa has never been one to let a grudge die quietly. Now, with his career roaring back to life, he’s dragged an old rivalry with Khamzat Chimaev out of storage and straight back into the spotlight.

The feud had cooled in recent months, buried under Costa’s own struggles and Chimaev’s uncertain future. Not anymore.

Costa, once tipped as a future champion, hit the wall hard after his first professional defeat to Israel Adesanya at UFC 253. That loss in a title fight didn’t just take his unbeaten record; it knocked the trajectory out of his career. What followed was a brutal skid: four defeats in five outings, the lone bright spot a win over a retiring Luke Rockhold that did little to silence doubts about his long-term prospects.

Unsure of how to arrest the slide, the Brazilian stepped away. A full year out of the cage. No noise, no headlines, just a fighter trying to figure out whether he still belonged at the sharp end of the sport.

When he came back, the answer was emphatic.

Costa returned looking sharper, leaner, and far more ruthless. He outclassed Roman Kopylov, then announced himself properly at light heavyweight with a savage head-kick knockout of previously unbeaten Azamat Murzakanov in April. That finish didn’t just win him a fight; it reset his narrative. From fading contender to live threat at 205.

He hasn’t fought since that statement win, but he’s not drifting. His sights are locked on one name.

Khamzat Chimaev

With rumors swirling about Chimaev abandoning middleweight and jumping straight to light heavyweight, Costa has made his stance clear: that path, he insists, leads straight into danger.

“I think that would be great for me,” Costa told Mr. Gamble. “It would be wonderful for him? I don't think it would be very good, no.”

The message is blunt. Come up, and you’ll pay for it.

Costa went further, drawing a pointed comparison to Alex Pereira’s unsuccessful foray into the heavyweight ranks. For him, Chimaev entertaining 205 carries the same kind of physical mismatch.

“I think for him it would be like Alex moving up to heavyweight, you know? I think the proportion is something similar, isn't it? The body type. I don't know. I think they're very light.”

It’s a technical argument wrapped in a challenge. Costa sees size, frame, and natural division as decisive factors. In his eyes, Chimaev at 205 wouldn’t be the marauding force fans have seen at welterweight and middleweight, but a smaller man in with bigger, stronger, more seasoned light heavyweights. Fighters like Costa himself.

The rivalry between the two has always felt combustible, built on clashing personalities and the promise of violence rather than any shared history in the cage. Now it has a new hook: a division, a direction, and a warning.

If Chimaev really does test the waters at light heavyweight, Costa is already waiting, convinced the move would be a gift to his own resurgence and a brutal reality check for one of the sport’s most talked-about names.